1. Field of the Invention
This invention relates to a computer readable medium having computer executable instruction for performing a communication performance analyzing, a communication performance analyzing apparatus and a communication performance analyzing method for analyzing the trend of data on the communication performance of a plurality of computers of a computation system in each execution period, the computation system being formed by connecting a plurality of computers by way of a network.
2. Description of the Related Art
The technique of raising the processing speed of scientific and technological computations by means of a computer system realized by connecting and parallelizing a large number of computers by way of a high speed network is known.
For such a computation system, it is necessary to verify that the computation system is configured properly and shows a satisfactory data transfer performance on the system level prior to verifying the efficiency of parallelization by means of real applications.
Conventionally, in such a verifying operation, the person who configured the system and/or a professional of verifying operations observes the communication time of each of the computers and visually checks the system to see that the average value and the maximum value of the communication times are not abnormal.
The expression of communication time data refers to data obtained by observing the communication time of each combination of computers held in a communication relationship. When N computers exist, the number of combinations of all the computers is N×(N−1)/2. Thus, the communication time data of a system having N computers refers to the data obtained by observing the communication time of each of the N×(N−1)/2 combinations of the N computers.
The communication time is observed after specifying the items of observation such as communication mode and communication data length. The communication mode is selected from a plurality of different modes such as a mode where the communication time of a combination of computers held in a communication relationship is observed after occupying the network and a mode where the network is shared even when making such an observation.
The communication data length is selected from a plurality of data lengths such as 2 B, 16 B and 128 B. The communication time is observed after specifying one of the communication modes, one of the communication data lengths and so on. For example, if there are N1 different communication modes and N2 different communication data lengths, it is possible to observe N1×N2 different sets of communication time data.
With the prior art, the average value and the maximum value are computationally determined for a set or a plurality of sets of communication time data and interpreted to verify the communication performance.
As a technique relating to the present invention, a technique invented for the purpose of providing new techniques of burying network data suited for browsing in a low dimensional space is known. This technique employs a process of computationally determining the improvement index for the position of burying each node toward an optimal placement, using the position of burying each of the nodes that are updated sequentially as object to be processed and an objective function that tends to approach to a value as each node approaches an optimal position on an assumption that a node directly connected to another node by a link is optimally placed when it is placed closer to the another node than a node not directly connected to the another node by a link, a process of determining if the operation of updating the position of burying each node is to be ended or not according to the improvement index and a process of updating the position of burying each node so as to make it approach an optimal placement, using the value led out from the objective function, when the operation of updating the position is not to be ended. With this arrangement, it is possible to realize a burying operation, truly conserving the connection relationships (see, for example, Patent Document 1: Jpn. Pat. Appln. Laid-Open Publication No. 2004-318739).
However, with the above-described prior art, visual performance verification of communication time data is accompanied by the following problems.    1) It is difficult to intuitively understand communication time data. For example, it is difficult to intuitively notice a computer that can highly possibly fall into trouble.    2) It is difficult to intuitively understand the overall tendency of communication time data when the number of computer is large. It is difficult to intuitively grasp if all the computers show a communication performance of a substantially same level or the communication performance of the computers show dispersions.    3) It is difficult to intuitively understand the relationship between the communication performance and the observation items when there are a number of observation items for the communication mode and/or the communication data length. For example, it is difficult to intuitively grasp if the communication performance is influenced significantly by the communication mode, by the communication data length and/or by the combination of a specific communication mode and a specific communication data length.    4) It is difficult to intuitively understand the relationship between each of a plurality of observation items and a combination of a large number of computers. For example, it is difficult to intuitively find out that there is a computer that performs poorly when the communication data length is short and/or that there is a computer that performs poorly in a specific communication mode.    5) It is difficult to intuitively comprehend the tendency of the communication time data of each computer on the basis of the communication time data for a combination of computers. For example, it is difficult to intuitively find out if the communication performances of all the computers are substantially at the same level or the communication performance of a specific computer is poor.    6) It is difficult to give priority to each of the computers when checking the computers for trouble. For example, it is difficult to give a score to each computer by computations in terms of the degree of normality or abnormality.    7) It is difficult to intuitively comprehend the relation of cause and effect between the observed values on communication time and the communication performance. For example, it is difficult to intuitively comprehend the relation of cause and effect for a normal communication performance or an abnormally poor communication performance of a computer when the communication performance of a specific observation item is found within a specific range.    8) It is difficult to intuitively understand the conditions of an observed value of communication time that characterizes a computer trouble. For example, when the communication performance of a specific observation item is found within a specific range, it is difficult to objectively and automatically grasp the conditions relating to the level of possibility of a computer trouble.    9) It is difficult to automatically and objectively detect a computer trouble or a fall in the communication performance of a computer when the computer system is in operation.